Short-period stellar activity cycles with Kepler photometry
arXiv:1506.05725 · doi:10.1088/0004-637X/807/1/109
Abstract
We study the short-periodic component of stellar activity with a cycle periods Pcyc up to 1000 days using the Kepler mission photometry of fast-rotating (rotational periods from 1 to 4 days) stars with spectra of M4V to F3V. Applying the originally developed two non-spectral methods, we measured the effective period of stellar cycles in 462 objects. The obtained results are in accordance with previous measurements by Vida et al. (2014), do not seem to result from a beating effect. The performed measurements of Pcyc cluster in a specific branch which covers the previously unstudied region in the Saar-Brandenburg (1999) diagram, and connects the branch of inactive stars with the area populated by super-active objects. It is shown that the formation of the discovered branch is due to the alpha-quenching effect, which saturates the magnetic dynamo and decreases the cycle periods with the increase of inverted Rossby number. This finding is important in the context of the discussion on catastrophic quenching and other heuristic approximations of the non-linear alpha-effect.
arXiv comment37 pages, 17 figures
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Cited by in corpus (5)
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- Stellar Cycles from Photometric Data: CoRoT Stars
- A New Method for Estimating Starspot Lifetimes Based on Autocorrelation Functions
- Stellar activity and rotation of the planet host Kepler-17 from long-term space-borne photometry